How to use the Windows Recovery Environment

Accessing WinRE

There are several ways to access the user interface of WinRE:

• Click Start, Power, then hold down the Shift key while you press Restart.
• Click Start -> Settings -> Update & Security -> Recovery. Under Advanced Startup, select Restart now.
• Boot to your Recovery DVD or USB stick. (Use the following link to create your own! You should always have access to Windows 10 Recovery media in case the need arises) – Media Creation Tool
• If the OEM (Original Equipment Manufacturer) of your computer configured a hardware recovery button, you can use that.

There are also two less-known access methods for WinRE:

• REAgentC (Even I didn’t know about this one!) – From an administrative command prompt, type in reagentc /boottore. Restart the device and you’re in!
• Use, at an administrative command prompt, the shutdown /r /o command. This will restart the PC into WinRE. (You can also do this remotely over your LAN. Append the /m \\computername switch to the end. e.g. If I want to reboot the remote computer (REINDERS1), I would type on my console: shutdown /r /o /m \\REINDERS1.)

Now that you’ve achieved the Zen level of WinRE (the main portal screen), what to do? Depending on the journey you took to get here, your options will differ. As an example, if you booted using a USB stick or DVD, you won’t see the Reset this PC option. Let us explore each option and harness the power:

Use a device

Even though you can use the built-into Windows 10 ‘Reset this PC’ option, you may want to COMPLETELY wipe the hard drive and install Windows from scratch. To guarantee the cleanest possible start, you can boot to a DVD or USB stick with Windows 10 installation media and install Windows 10. Some computers make it tricky to be able to boot into a ‘Boot Menu’ so you can choose what device to use. This is a nice, fool-proof method to get you there.

Troubleshoot

Thankfully over the years, the Windows development team has steadily been consolidating various tools into this one menu. Let’s explore each item, one by one.

• Reset this PC – This will allow you to reinstall Windows 10 and let you choose to keep your files or remove them before the reinstallation.
• Startup Repair – Through the magic of numbers, if Windows fails to boot twice, the third boot will kick off Startup Repair. This tool can fix a corrupt master boot record (MBR), a partition table, or boot sector. Stuff that was painstakingly tedious and HARD in hears past… Ask me how I know. And if you’re running Windows 10 version 1809 or newer, this tool will also automatically remove the most recently installed update before being unable to boot. Again, a lot of legwork automated and easy to use. Nice. Who could ask for anything more?
• Startup Settings – This allows you to adjust how Windows starts. You may recall running ‘msconfig’ from the command line in the past. This lets you turn on Safe Mode, turn on ‘debug’ logging, display more detailed boot info, etc.
  

• Command Prompt – This just so happens to be the most powerful tool in WinRE. You can use it to edit the Registry (be careful), copy files, run the ‘DISM’ commands and system file checker commands to test and verify the integrity of your Windows installation to name a few. I’ll describe the most useful options here:
  • Copying Files – You can use this to copy some crucial files off your failed Windows installation to your attached USB stick or drive for safekeeping. You can also run notepad.exe to make these steps a little easier! Click File, Open, and then select the files you want to copy, right-click on them and choose the Send to -> Your USB device name here. Very handy!
  • Chkdsk – We all know what chkdsk is used for. ‘Check Disk’ for errors. Just be sure to verify what drive letter is for what partition. When booted into WinRE, drive letter assignments can be difficult to decipher. Use this link to understand how to use BCDEdit to get the correct drive letters.
  • SFC – As I mentioned above, System File Checker will inspect at the bit-by-bit level every system file crucial to the normal operation (and booting) of Windows 10. If it finds an incorrect version of a file, it will restore it from a cute little safety deposit box, hidden deep within the recesses of your hard drive’s inner composite materials. That’s right.
  • DISM – An even more thorough check requires your PC have a wired Ethernet connection (access to the Internet). If it does, you can run this command to clean up the image of Windows 10 from an online source. This uses Windows Update to repair corrupted system files against a constantly updated online image also hidden deep within the recesses of the Microsoft Redmond campus nestled in the heart of the state of Washington. (and other geographic locations on this orb)

  • dism /image:c:\ /cleanup-image /restorehealth

  • Registry Editor – Even though the darkest wizards, probably Sauron himself, created The Registry in Windows, and continues to lay claim to its inherent dark sorcery, you have the ability (and permission!) to make changes with it in WinRE. Just type in regedit.exe. Again, fair warning. You can easily put your computer into an unhappy state and prevent it from booting correctly if you make a faux pa.
  • Uninstall Updates – This opens a simple menu that allows you to either ‘Uninstall the latest quality update (Monthly Cumulative Update) or ‘Uninstall the latest feature update’ (If you just upgraded to Windows 10 version 20H2, it will revert you to the version you upgraded from, say, Windows 10 version 1909)
  • UEFI Firmware Settings – As I mentioned earlier, this is an easy, no-nonsense way to get into the BIOS/UEFI firmware settings of your PC. Maybe you have to enable some hypervisor settings so you can enable the Hyper-V feature in Windows, or perhaps you need to disable the secondary CPU cache because of an odd hardware incompatibility with your webcam. This is all possible here and more!
  • System Restore and System Image Recovery – If your PC is configured with legacy system restore options or image-based recovery, this option is for you. You can use System Restore to restore the state of Windows from BEFORE you installed iTunes on your PC! 😉
  • Recovery Drive – As stated above, this is something you need to have on hand, always. In case your user’s PC doesn’t boot at all, you’ll need this to boot into WinRE and perform the steps in this article. You can also choose to back up system files to the recovery drive. This will take some time but will let you re-install to a completely blank hard drive. This is what I was talking about earlier when you want to install completely from scratch.

Managing WinRE

You do have the option of running this at an administrative command prompt to disable WinRE.

reagentc /disable

This is not recommended as some Windows 10 features will not work, including many in this blog post. Also, after the next Feature Update is installed, it will be re-enabled as it is required by the Windows Update engine for the upgrade process.

Permission and authentication

If you happen to be a Windows Insider, you may have noticed as of Build 19536, the default authentication requirements were adjusted to NOT require local administrative rights to use most of these tools. This allowed for passwordless accounts and Azure Active Directory accounts that weren’t backed up with a local admin account. If you manage devices using Intune (MDM), you can configure the Security/RecoveryEnvironmentAuthentication policy to require local admin access for these tools.

Other interesting tidbits

Booting into RAM

Just be aware that when using WinRE, you’re likely running on the X: drive. When you open a command prompt or use the command environment, it will default to the X: drive. This is temporary, running in RAM. Any files you happen to save to the X: drive will be gone when you reboot your PC!

BitLocker

Make sure you have the BitLocker recovery password for the volume you’re working on. Depending on some configuration settings and how you boot into WinRE, you may be asked for this key.

Recovery Partition Layout

In the past, Microsoft placed the recovery partition for WinRE before the main system, C: drive Windows partition. This proved difficult to update WinRE. As of Windows 10, version 20H1, they’ve officially specified during setup that the partition for WinRE comes last, as seen in my screenshot towards the top of this article.

Make sure you don’t assign any drive letters to this volume or copy any files to it. It needs to remain ‘frozen in time’ in order to operate properly when you most need it!

Conclusion

Well, now that is a lot to know! Again, Microsoft has done a wonderful job of bringing a lot of different tools and resources into one, cohesive interface to handle all your ugly situations of not being able to get into Windows. If you have any questions about any of the features here, feel free to leave me a comment!